What reasons can lead to a decrease in database performance when using indexes for update and insert operations?

Indexes speed up read operations but can slow down update and insert operations for several reasons:

• Additional operations during data modification: When inserting or updating a record, not only the table itself must be changed, but all related indexes must also be updated, which requires additional resources.
• Index fragmentation: Frequent updates can lead to index fragmentation, degrading performance.
• Number of indexes: The more indexes on a table, the more work is required for each write operation.
• Complex or composite indexes: Indexes with many columns or computed values require more time to update.

Therefore, when designing a database, it is important to balance the number and types of indexes, considering the load on read and write operations.